Discussion with mini review of the literature:
Furcation involvement is a major factor hindering the prognosis of molar
teeth because of the difficulty in maintaining an area free from dental
plaque. Root resection and/or amputation is a possible strategy for
managing this situation by creating an area that is more accessible for
oral hygiene measures. Several previous studies have evaluated the
long-term success of this procedure. 1920-25. Table 1 summarizes some of the studies
available in the literature with their main findings.
The success rate ranged from 100% 14,26 to 40%27; however, a systematic review published in 2009
reported the survival rate to range between 62%-100% over an
observation periods of 15-13 years28. A more recent
systematic review published during 2020 indicated an overall survival
rate of 38%–94.4% which is similar to that of scaling and root
planing and open flap debridement. 29 The difference
in success rates between studies can be attributed to several factors,
including the criteria for case selection, type of final restoration,
follow-up duration, and criteria for defining success.30
Derks et al. evaluated the long-term survival rates of root-resected
teeth over approximately 30 years. They reported a cumulative survival
rate of 90.6% for the first 10 years, which decreased considerably
thereafter, with a median survival duration of 20 years after root
resection. 31
Owing to the importance of proper case selection and careful performance
of the procedure for improving the overall survival rate, several
authors have attempted to define the essential criteria for determining
procedural success.
Newel attributed failures to residual root fragments and furcation lips
and ledges that were not properly identified and managed during surgery,32 while Carnevale et al. considered osseous
recontouring and apical repositioning of the flap essential for
procedural success. 33
Mjzoob and Kon stressed the importance of careful evaluation of the
procedure and proper planning for subsequent restorations because only
8% of root-resected molars have favorable periodontal support
postoperatively. 34
Park reported that teeth with >50% residual supporting
bone had higher survival rates. 35 In contrast, Lee et
al. reported an increased risk for procedural failure in teeth with
mobility ≥ grade 2 before root resection and removal of the supporting
bone. 27 Persistent mobility of any degree after
phase-one therapy and the involvement of two or more proximal surfaces
were considered contraindications by Klavan et al. 23
Rasperini presented a decision tree wherein root amputation/resection
was indicated only for cases with grade 3 furcation involvement with the
vertical component of the furcation not exceeding the middle third of
the root and attachment loss limited to only one root.36
The choice between maintaining a tooth with root amputation or replacing
it with a dental implant is debatable. Fugazzotto et al. compared the
success rates of root-resected molars to those of dental implants placed
in the molar region and found success rates ranging between
95.2%–100% over 15 years of observation, with cumulative success
rates of 96.8% for root-resected molars and 97% for implants.37 Zafiropoulos et al. reported a complication rate of
32.1% in root-resected molars compared to 11.1% in implants in the
molar region over approximately 4 years. 38 Similarly,
Kinsel et al. reported a 15.9% failure rate for root-resected molars
compared to 3.6% for single implants. 39
Higher failure rates for implants in the maxillary molar region are
attributed to the bone quality in that region. 40Simonis et al. reported complications in approximately 48.03% of
implants. 41 Therefore, all factors should be
considered and treatment options should be discussed with the
restorative dentist and presented to the patient before finalization of
the treatment plan.
In this case, root amputation successfully maintained the form and
function of the dentition for more than 10 years. We believe that
problems only started when the patient showed reduced compliance with
maintenance visits. Even though, we think that this treatment gave the
patient the chance to postpone bone grafting and dental implant
placement for better timing. Placing implants earlier might have led to
the development of peri-implantitis owing to the difficulties associated
with their maintenance.